Train-telephone system



1. M. MclLHANY AND E. K. K'lTTs.

TRAIN TELEPHONE SYSTEM.

APPLICATION FILED JAN. 30, 1918- Patented J uly 8, 1919.

2 SHtETSSHEET l- EEKiii J. M. MclLHANY AND E. K. KITTS.

TRAIN TELEPHONE SYSTEM.

APPLICATION FILED JAN. 30,19l8.

7 9 W W 1 a 9 W in m $2 JT II III I.

H T 1 l I I i I I I I I I II. dH mu JJ L M m U M D. 15A J x STATES PA NToF IoE JOHN MQMQILHANY m mmns'r 1: "sins, or BLUEFIELIl), WEST vmema.

TRAIN-TELEPHONE SYSTEM.

To all whom it may concern:

Be it known that we, JOHN M. MCILHANY and ERNEST K. Krrrs, citizens of the United States, residing at Bluefield, in the county of Mercer and State of West V1rgin1a, have invented certain new and useful Improve ments in Train-Telephone Systems; and we do hereby declare the following to be a full,

- clear, andexact descri tion of the invention,

such as will enable ot iers skilled in the art to which itappertains to make and usethe same.

This invention relates to improvements in.-

train telephone systems, and has for one of lts objects the provision of a device of this character whereby the occupant or occupants of one car can talk or communicatewith those of another car while thetrain or cars are in motion or standing idle.

Another object of this mventlon is to provide a telephone system in each car and so connected to the air line or system so that when the cars are coupled together in train formation the air line or system will convey the conversation from onetelephone system to another;

A further object of this invention is the simple, durable and efficient, and which may be manufactured and sold at a comparatively low cost.

With these and other objects in new as -will become more apparent as the description proceeds, the invention consists in certainnovel features of construction, combination and arrangement of parts as will be hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be hadto the following description and accompanying drawings in which Figure 1 is a. fragmentary side elevation of a train having a telephone system applied thereto, and constructed in accordance with my invention.

Fig. 2 is a fragmentary sectional view Specification of Letters Patent.

illustrating the means of connecting a tele Patented-July 8', 1919, Application filed Ianaury 30, 1918. se i n ing-51L a L I.

phone instrument to the air line or system of the train; F1 3 is a vertical sectional view ofthe telep one instrument, and a Fig. 4, is adiagrammaticalview of the w ring diagram of companion telephone systems upon a pair of cars of a train.

Referrin numeral 1 indicates .a train consisting of a caboose or car 2 coupled in train formation to a. locomotive. 3 consisting of the usual cab 4 and tender 5. We have elected to show our invention installed upon a train including the locomotive and caboose but may be readily installed on any of the other cars that may be used to form a train. The locomotive, cab'oose, and tender 5 are each provided with an air pipe 6 which are adapted :to convey and contain the air pressure of the brake systems of the cars (not2 shown) and which are connected together in the usual manner as illustrated at 7 The pipes 6 of the locomotive 3 and caboose 2 have branch pipes 8 connected thereto which have secured to their upper ends, substantially conical shaped housings or casings 9 which are secured to the locomotive and caboose by means of supporting brackets and on which are positioned the telephone instruments 11.

The telephone instruments 11 and the systems thereof are each identical in. construction and reference to one is thought suflicient for both. The telep-hone instrument 11 consists of the usual base 12 having formed thereon a hollow standard 13 carrying the usual transmitter 14. The hollow standard in detail to the drawings, the v 13 has pivoted therein the receiver supporting arm 14 carrying the usual receiver 15.

A contact member 16 is secured to the base tional contact 19 formed thereon and which is insulated therefrom by means of an insulating material 20. The contact arm 17 is:

normally urged in engagement with the contact member 16 by the weight of the receiver 15 upon the receiver supporting arm 14 and which will be disengaged therefrom. when the receiver 15 is removed from the receiver supporting arm 14 under the influence of the spring 21. Located upon the base 12 is a suitable circuit breaker 22.

An auxiliary receiver 23 is located in the housing or casing 9 and has formed thereon a suitable horn or funnel-shaped member 24. The auxiliary receiver 23 is of the same construction as that of an ordinary telephone receiver. An auxiliary transmitter 25 similar in construction to an ordinary telephone transmitter is located within the housing or casing 9. A conductor 26 is connected to the auxillary receiver 23 and to the contact 19 carried by the contact arm 18. Acontact 27 is located in the standard 13 of the telephone instrument 11 in close proximity to the contact 19 and has connected thereto a conductor 28 which is in turn connected to the transmitter 14 of the telephone instrument 11. A conductor 29 is connected to the transmitter 14 and to a battery or other electrical source 30. An induction coil 31 con sists of a core 32 having a primary winding 33 and a secondary winding 34. A conductor 35 is connected to the battery or electrical source 30 and to one end of the secondary winding 34. A conductor 36 1s connected to the conductor 35 and to one end of the primary winding 33. A conductor 37 is connected to the other end of the primary winding 33 and to the auxiliary receiver 23. A conductor 38 is connected to the secondary Winding 34 and to the auxiliary transmitter 25. A conductor 39 is connected to the auxiliary transmitter 35 and to the contact member 16 of the telephone instrument 11. A conductor 40 is connected to the contact arm 18 and to the receiver 15. A conductor 41 is connected to the receiver-15 and to the circuit breaker 22, which is; normally closedand is of the type of an ordinary switch which can be manually actuated.- A conductor 42 is connected to the circuit breaker 22 and to the conductor 29, whereby upon removing the receiver 15 from the rece ver supporting arm 14, the contacts 18 and 19 will move in engagement with the contact member 16 and contact 27 respectively completing electrical circuits from the receiver and transmitter of the telephone instrument 11 to the auxiliary receiver 23 and transmitter 25 so that a person talking into the transmitter 14', the sound waves will be carried to the auxiliary receiver 23 and the sound produced into the casing or housing 9. A per-- son at the other telephone system in the other car having the receiver removed from the receiver supporting arm will receive the sound waves through the air line or pipes 6 through the auxiliary transmitter to the re- -spect1ve receiver. hen a person is talking in to the transmitter 14 of one of the telephone instruments 11, the circuit breaker 22 is manually manipulated to break the circuit to the respective receiver 15, thereby prevent- 1,eos,91o I ing the persons own conversation being can ried back to the respective receiver.

Each of the telephone systems has a call 'and receiving signal 43 and 44 respectively.

The calling signal 43 is in the form of an ordinary electrical vibrating horn and is located within the housing or casing 9 along with the auxiliary receiver 24 and transmitter 25, and has connected thereto conductors 45 and 46. The conductor 45 is connected to a battery or electrical source 47 which has connected thereto a conductor 48. The conductor 48 is connected to a switch or push button 49 and which has the conductor 46 connected thereto whereby upon completing an electric circuit by closing the switch or push-button 49-, the calling signal 43 will be actuated. The receiving signal 44 is in the form of a telephone receiver having an enlarged horn so as to magnify the sound. The receiving signal 44 is located in the car in close proximity to the telephone instrument. A conductor 50 is connected to the conductor 38 and to the signal receiver-44. Aconductor '51 is connected to the signal receiver 44 and to a battery-or other electrical source 52. The battery. or other electrical source 52 has connected theretov a conductor 53 which is connected to the contact. arm 17 of the telephone instrument whereby an electric circuit is completed to the signal receiver 44 when the receiver 15 is upon the receiver supporting arm 14', thus making it possible when the signal 43 of one of the telephone-systems is actuated the auxiliary transmitter 25 of the other signal system will receive the sound wave and transmit itto the signal receiver 44 connected thereto, thus calling the other party to the telephone. The circuit breaker 22 of the telephone instrument 11 is constructed in accordance with an ordinary switch so that the circuit to the receiver 15v may be broken at any time by manually opening the same or when a person is talking into the transmitter preventing their own conversation from being received in the respective receiver 15.

Thetrain telephone system being of the aforedescribed type, permits the use of the ordinary airline or system of a railroad train to be employed for conveying the' sound waves from one telephone system to the other, or from one ear to the other by the pipes 6 containing air-pressure, permits the sound waves to be readily conveyed from one system to the other. =The auxiliary transmitters and receivers 25 and 23 are pro'- vided with apertures 54 to equalize the air pressure upon each side of their diaphragms. The apertures 54 being so located as they will permit air to the rear faces of the diaphragms. v

While we have shown and described the preferred embodiment of our invention, it will be understood that minor changes in construction, combination and arrangement of parts may be made Without departing from the spirit and scope of the invention, as claimed. i

Having thus described the invent-ion, What is claimed is A railway train telephone system including the air of the main line pipe of the air brake system as a conductor, housings connected to the main line pipe of theair brake system, telephone receivers and transmitters, auxiliary transmitters and receivers located in the housings, electrical means connecting the telephone receivers and transmitters to the auxiliary transmitters :and receivers, 15

electrical signaling means in said housings,

' and signal receivers electrically connected JOHN M. MCILHANY. ERNEST K. KITTS'. Witnesses:

J. L. SIMPSON, W. J. WooLwmE. 

